JPS6361851U

JPS6361851U -

Info

Publication number: JPS6361851U
Application number: JP15656186U
Authority: JP
Priority date: 1986-10-13
Filing date: 1986-10-13
Publication date: 1988-04-23

Description

[Brief explanation of the drawing]

第１図はこの考案の原理回路図、第２図は第一
の実施例を説明する原理回路図、第３図、第４図
は回線電圧の説明図、第５図、第６図は第２の実
施例を説明する原理回路図、第７図は従来の手段
の説明図である。１……通話回線、２，２０……検知器、２ａ，
２０ａ……出力端子、３……局交換機、４……加
入者装置。 Fig. 1 is a principle circuit diagram of this invention, Fig. 2 is a principle circuit diagram explaining the first embodiment, Figs. 3 and 4 are illustrations of line voltage, and Figs. The principle circuit diagram for explaining the second embodiment, and FIG. 7 is an explanatory diagram of the conventional means. 1... Call line, 2, 20... Detector, 2a,
20a... Output terminal, 3... Central exchange, 4... Subscriber equipment.

Claims

[Scope of Claim for Utility Model Registration] (1) A line condition detector equipped with a detector that is connected in parallel to a telephone line and determines the line condition by determining the polarity of the line voltage of the telephone line, A line state detector characterized in that a DC voltage having a polarity opposite to the polarity of the line voltage during the state is applied to the input side of the detector. (2) The line condition detector as set forth in claim 1 of the utility model registration claim, wherein the applied DC voltage is applied in parallel to the telephone line. (3) The line state detector as set forth in claim 1 of the utility model registration claim, wherein the added DC voltage is added as an input bias voltage of the detector. (4) The line condition detector as set forth in claim 2 of the utility model registration claim, wherein the input bias voltage is applied from one or two power sources.